If you choose to let the students work on computers, make sure that spreadsheet software compatible with MS Excel is installed and that the Excel file supplied with this activity is provided to them. Distribute the worksheets. They contain background information about how to construct and to interpret a climate chart.
Start a discussion about the different components of weather that we can measure. Students may come to the conclusion that temperature, wind and rainfall are the main contributors.
An additional discussion can be conducted on the following questions and topics.
Q: If you knew the current temperature and amount of rainfall, would you be able to determine the season of the year? If the students need help, remind them of the seasons.
A: The summer is warmer than the winter in many places on Earth, but there are also cool days during summer and rather warm days during spring. Additionally, the amount of rainfall can change considerably between consecutive days.
Q: What does it mean when we say that generally, summer is warmer than winter?
A: Correct answers would be ‘most of the time’, ‘on typical days’ or ‘on average’.
Q: With this in mind, how would you characterise seasons in terms of weather phenomena?
A: Seasons characterise periods during the year that on average are associated with a certain kind of weather.
Q: Can you describe different types of climate? What are the climatic differences between … and … (select any two regions with very different climates, e.g. southern Spain and London)?
A: London is rather rainy and mild, while southern Spain tends to be dry and warm.
Q: If London is characterised as being ‘rainy’, does it mean that it rains every day?
ACTIVITY 1: THE AVERAGE WEATHER
The students will now characterise the climatic conditions of a specific location, the Observatory of Jena (Jena is pronounced: [`je:na] or in English: yena) in Germany. In the end, they need a list of representative temperatures and precipitations for each month of the year. These values will be 30-year averages of individual weather data obtained for each day.
Table 2 provides daily mean temperatures and accumulated precipitation (rain) for June 2010. Ask the students the following question:
Q: What would be the typical temperature of that month in 2010? How would you calculate it?
A: The mean temperature is the average of all temperature measurements.
Let the students calculate the mean temperature and the total amount of precipitation from this. This table is also available as the ‘Task 1’ sheet in the Excel spreadsheet file provided. Choose whether the students should calculate the values manually using a pocket calculator or by means of the spreadsheet functions AVERAGE() and SUM(). The result will be added to the corresponding empty cells in Table 3 and the Excel sheet ‘Task 2’ for the year 2010. More information is given in the worksheet.
Table 2: Weather data obtained at the Jena Observatory from June 2010, including daily mean temperatures and accu-mulated precipitation.
Day | Temperature (°C) | Precipitation (mm) --- | --- 1 | 11.2 | 5.2 2 | 12.3 | 1.9 3 | 17.3 | 0 4 | 16.3 | 0 5 | 19.1 | 0 6 | 22.1 | 0.3 7 | 19.5 | 0.3 8 | 20.2 | 0 9 | 23.7 | 0.1 10 | 24.1 | 0 11 | 22.6 | 1.2 12 | 17.7 | 1.2 13 | 15.5 | 0 14 | 15.3 | 0 15 | 16.2 | 0 16 | 15.4 | 0 17 | 17.4 | 0 18 | 17.5 | 0 19 | 13.3 | 0.1 20 | 13.5 | 0 21 | 13.0 | 0 22 | 14.6 | 0 23 | 16.8 | 0 24 | 19.7 | 0 25 | 20.1 | 0 26 | 19.5 | 0 27 | 19.6 | 0 28 | 21.4 | 0 29 | 22.9 | 0 30 | 23.2 | 0
Expected results: The mean temperature is 18°C and the total amount of precipitation is 10 mm.
After completing this step, the students will now have to calculate the representative average weather data for June any years between 1981 and 2010. Table 3 lists the monthly average of the temperature and the monthly precipitation for the month of June between 1981 and 2010. Ask the students the following questions:
Q: How can you judge whether the result from the previous task is representative of any June?
A: Compare it with the values of other years.
Q: What are the highest and lowest values of the temperature and precipitation?
A: Lowest: 14.9°C, 10 mm; highest: 20.4°C, 118 mm
Q: What would be the typical temperature in June in any given year? How would you calculate it?
A: The long-term mean temperature, i.e. the average of temperature measurements over many years, e.g. 30 years.
Let the students calculate the mean temperature and precipitation from Table 3. This table is also available as the ’Task 2’ sheet in the Excel spreadsheet provided. Choose whether the students should calculate the values manually using a pocket calculator or software. The result will be added to the corresponding empty cells in Table 4 and the Excel sheet ‘Task 3’ for the month of June.
Table 3: Averaged weather data for the month of June obtained at the Jena Observatory from 1981 until 2010, including monthly mean values of temperature and monthly precipitation.
Year| Temperature (°C) | Precipitation (mm) --- | --- 1981 | 17.2 | 62 1982 | 17.9 | 48 1983 | 17.4 | 66 1984 | 15.3 | 89 1985 | 14.9 | 60 1986 | 16.6 | 62 1987 | 15.4 | 104 1988 | 16.4 | 57 1989 | 16.6 | 57 1990 | 16.8 | 118 1991 | 15.3 | 80 1992 | 18.4 | 39 1993 | 16.9 | 87 1994 | 17.7 | 73 1995 | 15.4 | 75 1996 | 16.6 | 34 1997 | 16.9 | 50 1998 | 18.0 | 62 1999 | 16.3 | 67 2000 | 18.4 | 37 2001 | 15.5 | 61 2002 | 18.4 | 45 2003 | 20.4 | 55 2004 | 16.5 | 46 2005 | 17.1 | 39 2006 | 17.7 | 39 2007 | 19.0 | 73 2008 | 18.3 | 43 2009 | 15.6 | 56 2010 | |
Expected results: The mean temperature is 17°C and the mean precipitation is 60 mm.
Table 4: Climate data based on weather data obtained at the Jena Observatory and averaged over 30 years.
Month | Temperature (°C) | Precipitation (mm) --- | --- January | 2.1 | 35 February | 2.2 | 34 March | 5.5 | 46 April | 9.4 | 45 May | 14.2 | 60 June | | July | 19.2 | 77 August | 18.5 | 65 September | 14.3 | 48 October | 10.0 | 38 November | 5.3 | 53 December | 2.4 | 46
From Table 4, let the students calculate the annual mean temperature and annual total precipita-tion. This table is also available as the ‘Task 3’ sheet in the Excel spreadsheet provided. Choose whether the students should calculate the values manually using a pocket calculator or the spread-sheet functions average and sum. The results are typically mentioned in the header of the climate chart to be produced during the next activity.
The annual mean temperature is 10°C and the annual total precipitation is 607 mm.
ACTIVITY 2: CLIMATE CHARTS
Climate charts are a useful tool to quickly grasp the basic climatic conditions for any given location. Introduce the principles of producing such a chart using the background information. The details are also available in the worksheet. The example of Rome (Table 1) is used to evaluate the student’s basic understanding of the concept. In addition, show Figure 5, which is the climate chart for Rome.
Let the students discuss the main features of the climate chart. This should be conducted along the following questions: - What do the blue and red curves represent? - Which are the months with the lowest and highest temperatures? - What are the seasons connected with those temperatures? - On which hemisphere do we experience summer/winter during these months? - Which are the months with the lowest/highest precipitation? - When does the blue curve (precipitation) fall below the red curve (temperature)? - What does this mean for the climatic conditions? When throughout the year is it humid or dry in Rome?
The red and blue curves represent the long-term average annual evolutions of temperature and precipitation, respectively. The lowest and highest temperatures are achieved in January and July, respectively. This means that January represents winter, while July is in the summer. From this, one can deduce that Rome is in the northern hemisphere. The highest and lowest precipitation can be expected in October and July, respectively. Since precipitation is the lowest during the hottest month, and the blue curve is below the red one from June until August, we can expect dry summers. With the wet autumn and winter months, Rome has a climate that is between the moderate climate of central Europe and the dry climate one experiences in Northern Africa. This is typical of a Mediterranean climate.
Based on the results from the previous activity summarised in Table 4, let the students create a climate chart for the Jena Observatory. The instructions from the worksheet are as follows: - Take the millimetre paper and draw the coordinate system for the climate chart. Use the one for Rome as a template. Make sure to leave some room for the header. - Make sure the scales reflect the values. - The scale for the precipitation must show values that are twice the numbers in the temperature scale in the opposite axis. - Add a header that lists the following items: name of the city and country, altitude, latitude, longitude, annual mean temperature and annual total precipitation - Begin with the temperature: add a red dot for each temperature value in the twelve months. - Connect the dots with a smooth red line. - Do the same for the precipitation but use blue. Here, the dots should be connected with straight lines. - If the blue line is above the red line, fill the area in between with blue vertical lines. - If the blue line is below the red line, colour this area yellow.
Details of the weather station:
Name: Jena Observatory (Germany)
Latitude: 50.9251° N
Longitude: 11.583° E
Altitude: 155 m
Discuss the results like you did for the Rome example. Ask the students how the climate of Jena compares to Rome.
From this chart, we can conclude that 1. Jena is in the Northern hemisphere as it is warmest in July, and this is similar to Rome. 2. Jena has a temperate climate. The precipitation roughly follows the temperature evolution. This is the opposite of the climate in Rome, where it is driest and hottest in the summer.
ACTIVITY 3: DERIVE YOUR LOCAL CLIMATE CHART (for advanced students only)
Weather data are available for almost any location and area around the world. Use the links below to find the suitable weather station from which you can derive the climate data that are needed to construct your local climate chart.
This tool permits easy access to 30-year averages between 1981 and 2010 for 9,800 weather stations in the USA. On this page, select ‘Monthly Normals’ and choose from the menu of federal states below. From the newly generates list, select the station that is nearest to your location. This produces a graph and a table. Remember that you need both temperature and precipitation data, which are not always available for all the stations.
Clicking on ‘View Station Details’ provides information needed for the header of the climate chart.
From the table, note the values for precipitation and average temperature. They have to be con-verted from inches into millimetres and from °F into °C. This can, for example, be done at https://www.metric-conversions.org
This page provides access to historic and current weather data for about 35 weather stations across the UK. It also provides instructions on how to load the data into MS Excel for subsequent statistical analysis.
Select the red dot that is nearest to your location. A window appears with the name of the station and its geographical coordinates. Click on ‘Historic station data’ to access the weather data. The linked file is a simple text file that has details on the weather station and lists the weather data averaged for every month of a given year. Among them is ‘rain’ in millimetres and the mean of the daily minimum and maximum temperatures. To get the mean temperature, just calculate the average of the two values. Then proceed as in Activity 2.
For details, please refer to the Readme file provided in the FTP folder.
The suitable data are located at
The file ‘KL_Monatswerte_Beschreibung_Stationen.txt’ lists the station id (needed to identify the data file), the duration of weather observations, altitude in metres, geographical coordinates, the station name and the federal state of each of the weather stations. The data are stored in the files labelled monatswerte_XXXXX_YYYYYYYY_ZZZZZZZZ_hist.zip.
Here, XXXXX is the station id, while YYYYYYYY and ZZZZZZZZ denote the temporal range of the data. Select the station with sufficient temporal coverage nearest to your location. The content of these files is explained in DESCRIPTION_...pdf at the top of the file list.
From the ZIP file, extract the file ‘produkt_monat_Monatswerte…txt’. From this file, you need the columns
MESS_DATUM_BEGINN: begin of measurement MESS_DATUM_ENDE: end of measurement LUFTTEMPERATUR: mean air temperature in °C NIEDERSCHLAGSHOEHE: precipitation in mm
Then proceed as in Activity 2.
Compare the results with your own experience. Do the temperature and precipitation meet your expectations? How do they compare to the other locations, Rome and Jena? Why do you think this might be? Please discuss your conclusions!